Expansible shaft



1950 L. L. COLLARD 2,520,126

EXPANSIBLE SHAFT Filed Jan. 50, 1948 2 Sheets-Sheet l INVENTOR. LEWIS lCO LLARD ATTORNEY Aug. 29, 1950 L. L. COLLARD EXPANSIBLE SHAFT 2Sheets-Sheet -2- Filed Jan. 50, 1948 INVENTOR. LEWIS L. COLLARD ATTORNEYPatented Aug. 29, 1950 EXPANSIBLE SHAFT Lewis L. Collard, Camas, Wash.,assignor to Crown Zellerbach Corporation, San Francisco, Calif acorporation of Nevada Application January 30, 1948, Serial No. 5,381

8 Claims.

This invention relates in general to winder shafts and cores, and, inparticular, to shafts on which webs of sheet material such as paper maybe wound.

More specifically, this invention relates to expansible winder shaftsfor rolls of paper.

. It has been customary in the past to use comparatively heavy cardboardtubes as cores for the winding of rolls of paper, the tubes or coresbeing mounted on expanding chucks or shafts during the windingoperation, and the cardboard core then becoming a permanent part of thefin ished roll of paper. More recently it has been found that such innercores or tubes of cardboard are generally unnecessary if the paper iswound tightly on a metal shaft or core, provided such metal shaft orcore is so constructed that it can be withdrawn from the roll, in asmuch as the center of a tightly wound roll of moderately heavy paperwill retain its shape and position for the roll without requiring ancore to be kept therein. Accordingly, a number of paper mills are nowfollowing the practice of winding paper directly on expanded shafts orcores of different types and then subsequently removing such shaft orcore from the roll after the winding has been completed. The dispensingwith the cardboard core or tube for paper rolls results in considerablesaving, as apparent.

The object of the present invention in general, is to provide animproved expansible shaft adapted particularly for having a roll ofpaper Wound directly thereon.

A further object of this invention is to provide an expansible shaftwhich will have an expansible outer shell formed of metal sections whichar so arranged and mounted that the effective outside circumference ofthe shell can be quickly and easily expanded in preparation for thewinding of the paper on the same and can be quickly and easilycontracted and withdrawn from the roll when the winding is completed.

A still further object of this invention is to provide an improvedexpansible shaft of the type above indicated in which the expansion orcontraction of the outer surface or shell sections of the shaft will becontrolled by pneumatic pressure.

Whil the idea of pneumatic expansible shafts for paper rolls is not new,heretofore with shafts of this type the expansible rubber tubes or ringshave been so mounted as to have direct contact with the inside of thepaper roll or core. This causes Wear on the outer surfaces of the rubberelements and increases the liklihood of blowouts occurring. Anadditional object of this invention is to providea pneumaticallyxpansible shaft in which the rubber tubes or rings will be entirelyprotected by metal elements so as to avoid any direct contact betweenthe rubber tubes or rings and the paper.

These objects and other advantages I attain by constructing my improvedexpansible shaft substantially as illustrated in the accompanyingdrawings and as hereinafter briefly described with reference to thedrawings.

In the drawings:

Fig. l is anelevation of the entire expansible shaft, showing the samein expanded position, but with the roll of paper omitted therefrom forthe sake of clarity;

Fig. 2 is a'vertical longitudinal section of the expanded shaft drawn toa larger scale with the paper roll supported thereon indicated by brokenlines;

Figs. 3, 4, 5 and 6 are transverse sections of the shaft taken on thevertical planes indicated by the lines 33, 44, 55 and 66 respectively ofFigure 2, but drawn to a still larger scale, all these figures showingthe shaft in expanded position; and

Fig. 7 is a section on the same vertical plane as Fig. 4 but showing theshaft contracted.

Referring first to Figure 2, the main body portion of the shaft consistsof an inner metal tube H] which extends the full length of the shaft.One end of the tube It] is sealed, for example,

by means of a plug as indicated at H. An air inlet valve 12, of the typeused for automobile tires, is mounted in th other end of the tube It]and is adapted to be connected by means of the usual air hose (notshown) to a source of air under pressure.

On the same end of the tube In as the air inlet valve 12, there ismounted an air release valve consisting of a valve core l3, having aninwardly extending channel l4 adapted to register with a perforation inthe wall of the metal tube It), and an air release valve handle orsleeve l5, rotatably mounted on the core l3 and so arranged that the airexhaust channel M can be opened or closed by a slight turn of the handleor sleeve IS.

A journal I6 is firmly secured on the outside of the tube In adjacentthe release valve core 13, and another journal H is secured on theopposite end of the tube Ill.

The outer surface of my expansible shaft is composed of threelongitudinally-extending cylindrical surface segments l8. (See alsoFigs. 3,

4 and 5.) Each of these segments I8 carries a plurality ofrigidly-mounted pins l9 extending radially inwardly from the insidesurface of the segment, as shown in Figs. 2 and 5. At spaced intervalsalong the tube In positioning collars 20 are fixedly secured and thesepositioning collars are provided with radially-extending recesses 2|which slidably accommodate the pins l9. Thus the cylindrical surfacesegments l8 may move radially outwardly from the perimeters of thepositioning collars 2!] and in this manner may move outwardly orinwardly with respect to the tube I8, but are held against anylongitudinal movement by the sliding pins 18 within the recesses 2|.

Each of these surface segments I8 is also secured at its inside surfaceto a plurality of retaining rings 22, The shape of these retaining ringsis shown in Figs. 3 and 4. Each retaining ring has an elongated centeropening 23, the minor dimension of which is slightly greater than theoutside diameter of the metal tube ill and the major dimension of whichis considerably greater. Approximately two-thirds of the rim of eachr'etaining ring is of reduced width, as shown in Fi s. 3 and 4, thewidth of the remaining portion being approx mately the same as theradial width of the positioning collars 29. Each retaining ring isprovided with spring means, such as the coil spring 2!. (Fig. 4) whichis so arranged as to tend to pull the wider rim portion of the retainingring 22 (and therewith the surface segment 18 which is attached to theretaining ring at the wider rim portion) inwardly as far as permitted bythe cent r opening 23 A plurality of inflatable rubber tubes or rings 25are mounted around the metal tube in at spaced intervals. Each of theseinflatable rubber rings 25 is connected to the inner metal tube It] byan air channel nipple assembly 26 (Fig. 6). so arran ed as to p rmit airto pass freely from the interior of the tube Ill into the rubber rings22, or to permit the air to pass in the reverse direc-- tion from therubber rings into the tube H), depending upon the air pressure in thetube I 0.

Thus, when air is forced into the tube Iii, the rubber rin s 25 will beinflated, and by pressing against the interior of the surface segmentsI8, will force the latter to move to their outer expanded position: andwhen the air pressure within the tube H! is relieved, reducing theinflation of the rubber rings 25, the springs 24 on the retaining rings22 will cause the surface segments l8 to be pulled in to their inward orretracted posiion.

Along one edge on the interior face of each surface se ment IS a thinflexible metal slide 21 is secured which slidably engages the inner faceof the next adjacent segment 18 along its edge and thus bridges thelongitudinal gap between the edges of the two surface segments when thesurface segments are in expanded position. The purpose of these thinmetal slides 21 is to provide protective covers for the rubber rings 25in the gaps between the edges in the surface segments l8 and thus toprotect the rubber rings and prevent any possibility of blowoutsoccurring in these gaps when the inflation of the rubber rings hasforced the surface segments l 8 into expanded position. Similarly, toprevent blowouts occurring at the ends of the rubber rings 25 inside thesurface segments when the shaft is in expanded position, I provide anadditional series of three thin protective metal rings or shims 28 (Fig.2), at each end of each rubber ring. These protective end rings or shims28 are exactly the same shape and size as the retaining rings 22previously described, and each protective end ring is attached to one ofthe surface segments l8. Springs are omitted from these end protectiverings in order that the three rings of each set can be pressed closetogether, slidably bearing on each other, and thus collectively formingan effective adjustable thin metal wall at each end of the rubber rings.These sets of protective rings 28 are placed between the positioningcollars 20 and the corresponding ends of the rubber inflatable rings.

The entire expansible shaft is supported for rotation in any suitablemanner. For example, the shaft may be supported on a pair of pedestals29 and 30, one at each end of the shaft, as illustrated in Figs. 1 and2. These pedestals have suitable bearings 3| in which the journals l6and I! rest. Preferably, a hinged cap 32, having a bearing 33 on itsinner side, extends over the upper half of the journal 16 and ishingedly secured on the pedestal 29 so as to hold the shaft in place onthe pedestal and prevent any longitudinal movement of the shaft when theshaft is mounted for rotation. Any suitable means for rotating the shaftwhen the shaft is positioned on the pedestals 29 and 30 may be employedas desired, such means not being shown in the drawings, in as much asthe same does not form any part of this invention.

The manner of operatin my expansible shaft is as follows: The valve I2is connected to a source of compressed air (the exhaust valve control l5being closed), and the rubber rings 25 are inflated until the surfacesegments l8 are firmly held in their expanded position. The inflating ofthe shaft may be done either when the shaft is .in rotatable position onthe supporting pedestals 29 and 30, or may be done before the shaft ismounted thereon, whichever is more convenient. The hose or other meansby which air under pressure is delivered to the shaft is thendisconnected from the shaft and the shaft is then ready to have thepaper wound on it. The shaft remains in its expanded position until thewinding of the paper upon it has been completed. The outer end of thewound paper is then fastened down on the roll, the shaft and roll arethen lifted from the supporting standards, and the roll with the shaftstill secured therein is set on a table for the removal of the shaft.When the shaft is to be removed from the roll, the operator turns theexhaust valve control l5 so as to open the exhaust valve and producedeflation of the shaft. This immediately results in causing the surfacesegments 18 to be returned to their retracted position, whereupon theshaft is easily slid out from the center of the paper roll. The shaft isnow ready to be inflated again and used for the winding of the secondroll.

I claim:

1. In an expansible shaft of the character described, an inner metaltube, an air valve connected with said tube, means for preventing escapeof air from said tube, a plurality of iongitudinally-extendingcylindrical surface segments on the outside of said tube and spaced fromsaid tube, a plurality of pins extendin radially inwardly from theinside face of each of said surface segments, positioning collarssecured on said tube, radially-extending recesses in said collars forslidabl accommodating said pins, means limiting the radial movement ofsaid surface segments with'respect to said tube, a plurality ofinflatable resilient rings axially spaced about said tube inside saidsurface segments, a channel connecting each of said inflatable ringswith the interior of said tube, and means mounted on longitudinal edgesof said surface segments so arranged as to extend over the gaps betweensaid surface segments when said surface segments are in expand-edposition to prevent blowouts occurring in said inflatable rings at suchgaps.

2. In an expansible shaft of the character described, an inner metaltube, an air inlet valve located at one end of said tube, a sealing plugat the other end of said tube, three longitudinallyextending cylindricalsurface segments on the outside of said tube and spaced from said tube,a plurality of rigidly-mounted pins extending radially inwardly from theinside face of each of said surface segments, positioning collarssecured on said tube, radially-extendingrecesses in said collars forslidably accommodating said pins, retaining rings on said tube, each ofsaid retaining rings having an elongated center opening permittingmovement of the retaining ring in a direction perpendicular to the axisof said tube, each surface segment secured to a plurality of saidretaining rings, a plurality of inflatable rubber rings axially spacedabout said tube inside said surface segments, a channel connecting eachof said inflatable rings with the interior of 0 said tube, and slidesmounted on longitudinal edges of said surface segments so arranged as toextend over the gaps between said surface segments when said surfacesegments are in expanded position to prevent blowouts occurring in saidinflatable rings at such gaps.

3. In an expansible shaft of the character described, an inner metaltube eXtending the full length of the shaft, an air inlet valve locatedat one end of said tube, a sealing plug at the other end of said tube,an air exhaust valve carried by said tube, threelongitudinally-extending cylindrical surface segments on the outside ofsaid tube and spaced from said tube, a plurality of rigidly-mounted pinsextending radially inwardly from the inside face of each of said surfacesegments, positioning collars secured on said tube, radially-extendinrecesses in said collars for slidably accommodating said pins, retainingrings on said tube, each of said retaining rings having an elongatedcenter opening permitting movement of the retaining ring in a directionperpendicular to the axis of said tube, each surface segment secured toa plurality of said retaining rings, said pins, collars, recesses andrings combining to permit restricted radial movement of said surfacesegments with respect to said tube, springs associated with saidretaining rings exerting a force to pull said surface segments inwardlyas far as permitted by said center openings, a plurality of inflatablerubber rings axially spaced about said tube inside said surfacesegments, a channel connecting each of said inflatable rings with theinterior of said tube, slides mounted on longitudinal edges of saidsurface segments so arranged as to extend over the gaps between saidsurface segments when aid surface segments are in expanded position toprevent blowouts occurring in said inflatable rings at such gaps, andmeans at the ends of said inflatable rings to guard against blowouts atsaid ends of said inflatable rings.

4. An expansible winder shaft of the character described comprising aninner metal tube extending the full length of the shaft, meansassociated with the ends of said tube for mounting saidshaft forrotation, an air inlet valve located. at one end of said tube, a sealingplug at the other end of said tube, an air exhaust valve carried by saidtube, a plurality of longitudinally-extending surface segments on theoutside of said tube and spaced from said tube, a plurality of pinsextending radially inwardly from the inside face of each of said surfacesegments, positioning collars secured on said tube, radially-extendingrecesses in said collars for slidably accommodating said pins, retainingrings on said tube, each of said retaining rings having an elongatedcenter opening permitting movement of the retaining ring in a directionperpendicular to the axis of said tube, each surface segment secured toa plurality of said retaining rings, said pins, collars, recesses andrings combining to permit restricted radial movement of said surfacesegments with respect to said tube, springs mounted on said retainingrings exerting a force to pull said surface segments inwardly as far aspermitted by said center openings, a plurality of inflatable rubberrings axially spaced about said tube inside said surface segments, achannel connecting each of said inflatable rings with the interior ofsaid tube, slides mounted on longitudinal edges of said surface segmentsso arranged as to extend over the gaps between said surface segmentswhen said surface segments are in expanded position to prevent blowoutsoccurring in said inflatable rings at such gaps, and adjustable metalwalls at the ends of said inflatable rings to guard against blowouts atsaid ends of said inflatable rings.

5. In an expansible winder shaft of the character described, an innermetal tube, an air inlet valve connected with said tube, a plurality oflongitudinally-extending cylindrical surface segments on the outside ofsaid tube and spaced from said tube, a plurality of rigidly-mounted pinsextending radially inwardly from the inside face of each of said surfacesegments, positioning collars secured on said tube, radially-extendingrecesses extending inwardly in said collars for slidably accommodatingsaid pins, means limiting the radial movement of said surface segmentswith respect to said tube, and a plurality of inflatable resilient ringsaxially spaced about said tube inside said surface segments, a channelconnecting each of said inflatable rings with the interior of said tube.

6. In an expansible winder shaft of the character described, an innermetal tube, an air inlet valve connected with said tube, a plurality oflongitudinally-extending cylindrical surface segments on the outside ofsaid tube and spaced from said tube, means connecting said surfacesegments and said tube permitting radial movement of said segments withrespect to said tube, retaining rings on said tube, each of saidretaining rings having an elongated center opening permitting movementof the retaining ring in a direction perpendicular to the axis of saidtube, each surface segment secured to a plurality of said retainingrings, and a plurality of inflatable resilient rings axially spacedabout said tube inside said surface segments, a channel connecting eachof said inflatable rings with the interior of said tube.

7. The combination set forth in claim 6 with the addition of springsmounted on said retaining rings and on opposite sides of said openingsand exerting a force to pull said surface segments inwardly as far aspermitted by said center openmgs.

' 8. In an expansible winder shaft of the character described, an innermetal tube, an air inlet valve connected with said tube, a plurality oflon gitudinally-extending cylindrical surface segments on the outside ofsaid tube and spaced from said tube, means connecting said surfacesegments and said tube permitting radial movement of said segments withrespect to said tubev while holding said surface segments againstlongitudinal movement on said tube, means limiting the radial movementof said surface segments with respect to said tube, a plurality ofinflatable resilient rings axially spaced about said tube itside saidsurface segments, a channel connecting each of said inflatable ringswith the interior of said tube, means mounted on longitudinal edges ofsaid surface segments so arranged as to extend over the gaps betweensaid surface segments when said surface segments are in expandedposition to prevent blowouts occurring in said inflatable rings at suchgaps, and adjustable 8 metal walls at the ends or said inflatable ringsto guard against blowouts at said ends of said inflatable rings.

LEWIS L. COLLARD.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 749,114 Surmann et a1. Jan. 5,1904 1,225,929 Crabtree May 15, 1917 1,492,291 Giovannoni Apr. 29, 19242,145,806 Schnedarek Jan. 31, 1939 2,289,519 Randall July 14, 1942FOREIGN PATENTS Number Country Date 8,543 Great Britain Apr. 22, 1896

